Prenatal programming of mental illness: current understanding of relationship and mechanisms.

The British epidemiologist Dr. David J. Barker documented the relationship between infant birth weight and later onset of hypertension, coronary heart disease, insulin resistance, and type II diabetes. A stressful in utero environment can cause long-term consequences for offspring through prenatal programming. Prenatal programming most commonly occurs through epigenetic mechanisms and can be dependent on the type and timing of exposure as well as the sex of the fetus. In this review, we highlight the most recent evidence that prenatal programming is implicated in the development of psychiatric disorders in offspring exposed to maternal stress during pregnancy. Methodological differences between studies contribute to unavoidable heterogeneity in study findings. Current data suggest that fetal exposure to maternal hypothalamic-pituitary-adrenal axis dysregulation, excessive glucocorticoids, and inflammation with resulting epigenetic changes at both the placental and fetal levels are important areas of continued investigation.